April 13, 2010

The Scientist: Ronald Hoy

For star-crossed lovers, their favorite love songs may come from the flamboyant melodies of masterful composers, like Antonio Vivaldi or Ludwig van Beethoven. But for Prof. Ronald Hoy, neurobiology and behavior, love songs are as natural as sound itself. He studies the animal movement and communication.

He focuses specifically on a class of behaviors called “central rhythms,” rhythmic movements performed by an animal to produce signals for communication. These rhythms are caused by neural systems called “central rhythm generators.” Many types of animals possess these central rhythm generators, from complex humans to insects.

In the same way that humans vibrate their vocal cords to produce speech, other animals use motions to communicate.

Recently, Hoy discovered the mechanism of mosquito communication.

According to Hoy, the movement of their wings in flight creates “love songs.” A mosquito tests its potential mates by changing the frequency of its wing movements. If the potential mate can match another frequency with its own “wing tone,” the duet may facilitate mating.

Of course, in order for acoustic communication to work, all members of the species must efficiently recognize and accurately interpret the signals. Central rhythm generators underlie the co-evolution of signal emitters and receivers.

“Evolutionary processes have driven the perceptual apparatus and the production apparatus so that they’re nicely tuned.”

The tachinid fly lays its eggs inside crickets. “We were studying this fly’s ear out of curiosity driven issues,” Hoy said. “How does a fly find a cricket?”

In collaboration, Hoy found that the fly evolved a new, directionally sensitive ear.

By translating this concept into a silicon model, the team created a very small, directionally sensitive microphone. This particular piece of “biomimicry,” or biology-inspired technology, can potentially improve hearing aids and cell phones. Because the microphone is directionally sensitive, it may reduce the level of ambient noise in a phone conversation.

Hoy, a music lover, finds inspiration in the works Beethoven and Vivaldi, who incorporated nature into their music.

“I’m very interested in the sounds that animals make, and how they’re represented in the realm of music.” Hoy said.

He is particularly interested in the music of French composer and ornithologist, Olivier Messiaen, who incorporated the songs of specific birds into his works. However, many ornithologists failed to identify the bird calls because, as Hoy asserted, Messiaen transposed, stretched or compressed the sounds to fit them.

“It’s a hobby to recover the birds in Messiaen’s music. I do this with a tape recorder, the same way that he probably used it to transcribe them, and I find that if I make the proper adjustments on the tape recorder, I find Messiaen’s birds in his compositions.”

“Communication acts are tuned in some way, tuned to some rhythm, and one of my lifelong interests has been to understand the rhythmic basis of communication acts.” Central rhythm generators make it possible for animalsto coordinate the meaningful movements that allow them to communicate.

Related

As her second five-year term comes to an end in June, Susan Henry, the Ronald P. Lynch Dean of the College of Agriculture and Life Sciences at the University, is planning to step down. The interview process for the new dean concluded Monday.